The bartender offers him a warm smile and says, "For you, no charge".
or
Because all the fans left!
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When it came time to pay, the skunk didn't have a scent, the deer didn't have a buck so they put the meal on the duck's bill.
or
Seven. One to install the new bulb and six to figure out what to do with the old one for the next 10,000 years.
or